Conventionally, a sewing machine that performs zigzag sewing has a needle bar that holds a sewing needle having an upper end axially attached to a sewing machine body and attached so as to be oscillatable like a pendulum, a vertical hook provided so that the direction of rotation is approximately parallel with the sewing direction and that has a point that catches the thread loop of the sewing needle, a rotary shaft that rotates the vertical hook, and an operating means that moves the sewing needle and the vertical hook reciprocatingly at the same time (for instance, see Patent Documents 1 to 4).
In addition, another sewing machine that performs zigzag sewing has a needle bar that holds a sewing needle having an upper end axially attached to a sewing machine body and attached so as to be oscillatable like a pendulum, a vertical hook provided so that the direction of rotation is approximately perpendicular to the sewing direction and that has a point that catches the thread loop of the sewing needle, and a rotary shaft that rotates the vertical hook (for instance, see Patent Document 5).
Further, a still another sewing machine that performs zigzag sewing has a needle bar that holds a sewing needle having an upper end axially attached to a sewing machine body and attached so as to be oscillatable like a pendulum in the direction approximately parallel with the sewing direction, a vertical hook provided so that the direction of rotation is approximately parallel with the sewing direction and that has a point that catches the thread loop of the sewing needle, and a rotary shaft that rotates the vertical hook (for instance, see Patent Document 6).    Patent Document 1: Japanese Patent Application Publication (JP-B) No. 28-3533    Patent Document 2: Japanese Patent Application Publication (JP-B) No. 30-7784    Patent Document 3: Japanese Patent Application Publication (JP-B) No. 31-791    Patent Document 4: Japanese Utility Model Application Publication (JP-Y) No. 43-15068    Patent Document 5: Japanese Patent Application Publication (JP-B) No. 44-8711    Patent Document 6: Japanese Patent Application Publication (JP-B) No. 7-28976